ruby-on-rails – Rails 4.模型中的国家验证

validates :country,inclusion:{in:Carmen::Country.all.map(&:code)}

但如果这就是你所需要的,那么countries gem也可能运作良好.有了你可以做的国家

validates :country,inclusion:{in:Country.all.map(&:pop)}

要么

validate :country_is_iso_compliant

def country_is_iso_compliant
  errors.add(:country,"must be 2 characters (ISO 3166-1).") unless Country[country]
end

更新

对于Region和State,您可以像这样同时验证所有3个.

validates :country,:region,:state,presence: true
validate :location


def location
  current_country = Country[country]
  if current_country
    #valid regions would be something Like "Europe" or "Americas" or "Africa"  etc.
    errors.add(:region,"incorrect region for country #{current_country.name}.") unless current_country.region == region
    #this will work for short codes like "CA" or "01" etc.
    #for named states use current_country.states.map{ |k,v| v["name"}.include?(state)
    #which would work for "California" Or "Lusaka"(it's in Zambia learn something new every day)
    errors.add(:state,"incorrect state for country #{current_country.name}.") unless current_country.states.keys.include?(state)
  else
    errors.add(:country,"must be a 2 character country representation (ISO 3166-1).")
  end
end

虽然地区似乎没必要,因为你可以从国家这里暗示这一点

before_validation {|record| record.region = Country[country].region if Country[country]}